Windows Vista "Superfetch".......It's In There....!!
Vista "prefetchs" applications it thinks you're going to use in advance, and leaves them running in RAM until you launch the application, The quantity of available available RAM will always appear lower in Vista than XP.
However, should you choose to summon different apps than the ones Vista has chosen, the OS will release the memory needed immediately to those tasks.
Vista's required memory for it's own needs is higher than XP's. (For that matter, XP needs more than the previous versions of Windows). Accordingly, memory usage will always be higher in Vista than XP. However, due to the prefetch, it's not as much higher as it appears.
Since, the machine shows 1.13 GB in use, I'm guessing that there's likely 2GB installed,which should be plenty.
Your CPU idle usage, is slightly higher than would be the case in XP, but nothing that should cause concern. This is dependent on the number of startup apps running. Resident security applications consume quite a few clock cycles as well.